Process for coloring organic fibers or articles such as skins, furs, paper, etc., consisting of animal and vegetable fibers



Patented I July 2, 1929.

UNITED STATES 1,719,159 PATENT OFFICE.

NIKOLAI WOROSHTZOW, OF BERLIN, GERMANY.

PROCESS FOR No Drawing.

This invention relates to processes for coloring organic fibers whether woven, loose or manufactured products or articles such as skins, furs, paper etc. consisting of animal and vegetable fibers.

Aromatic nitro-compounds have hitherto only been used very little for the coloring of fibers of all kinds. Such compounds have hitherto been chiefly used for producing a few yellow dyes, dinitro or polynitro derivates of certain phenols and amines having been chiefly employed for this purpose.

I have discovered that certain nitro-compounds of the naphthalene series and particularly such contain in their compounds, in addition to the nitro-group, one or more sulfonio acid-groups, and which in themselves do not posses any dyeing properties, are capable of producing pleasingtints, ranging from brown to dark brown on fiber articles,

if the article to be colored or dyed such as,

paper, fur or the like, is impregnated with the nitro-compound in question and is exposed to sunlight after drying. The parts of the material or article prepared in the aforesaid manner which are exposed to the light assume after a short time pleasing dark tints. The beauty of the tints can be increased and the time of exposure to the light can be simultaneously shortened if, instead of treating the fibrous materials with nitro-compounds only, a mixture ofnitro-compounds with aromatic amines is used. The amines may be employed in a free condition or in the form of a salt. Particularly suitable forms have been found to be aniline, its homologues and substitution derivatives, phenylendiamines, monoamines and diamines of the naphthalene series etc. When these amines are added tints ranging from dark to black are obtained.

As the initial substances used for treating the fibers can be removed only from the parts that have not been exposed, while the dyeing I agent adheres firmly to the parts that have been exposed to the light, the novel process enables photographic pictures to be produced without the aid of metal salts. The dyestuii formed does not fade at all when exposed to light so that the pictures do not change when they are exposed to light after they have been washed.

As the fibrous articles are treated with solutions of the 11itro-compoundsand are exposed to light at ordinary temperatures the processes can be advantageously employed for COLORING ORGANIC FIBERS OR ARTICLES SUCH AS SKINS, FURS, PAPER,

ETQ, CONSISTING OF ANIMAL AND VEGETABLE FIBERS.

Application filed June so, 1925. Serial m. 40,686.

Emmple 1.

W001 is impregnated at an ordinary temperature with a three per cent solution of 1 nitronaphthalene -7 sulfonic acid, then treated in the absence of actinic rays, and afterwards exposed to sunlight. After an exposure of one quarter to a full hour, accord mg to the intensity of the light, a dark brown color is obtained which is perfectly fast or unchangeahle. If instead of nitronaphthalene-sulfonic acid a solution containing, in 100 parts, three parts of l-nitronaphthalene- 7-sulfonic acid and 0.5 parts aniline hydrochlorid is employed the eflect of the light is completed in a shorter time and a black tint is obtained. l-nitronaphthalene-G-sulfonic acid, l-nitronaphtludene-S-sulfonic acid, 1.6- dinitro-naphthaleue-lS-disulfonic acid and other nitroand di nitro-11aphthalene sulfonic acids behave similarly.

Example F3.

A white skin is treated with a five per cent solution of 1.G-dinitro-naphthalene-4.8-disulfonic acid with the aid of a brush or by in'unersion and then exposed after drying to sunlight. A brown color is thus obtained which can be darkened by chroming.

' If the skin is treated, after impregnation with dinitro-naphthalene-disulfonic acid and the transparent parts of the screen when the.

- washed away with water or a weak solution of sodium hydrate or sodium carbonate.

The 1.6-dinitro-4.8-disulfonic acid can be replaced by other dinaphthaleneor mononaphthalene-sulfonic acids. Similarly the paraphenylendiamine can be replaced by other aromatic diamines or monoamines.

Example 3.

A sheet of paper that has been prepared by coating it with gelatine is treated with a 3 to 5 er cent solution of l-nitro-naphthalene- 8-su fonic acid, this solution being applied in any suitable manner as by a brush. After drying the paper is exposed to sunlight through a photographic negative. In this manner a photographic picture is obtained which is fixed by washing the paper with water or a weak solution of sodium hydrate or sodium carbonate. Darker or black tones are obtained by preparing the paper with nitro-naphthalene-sul fonic acid and at the same time with aniline hydrochloride or paraphenylendiamine hydrochloride or the like. By this means the effect of the light is also accelerated. An acceleration is also obtained if the addition of amine is replaced by some metal salts such as cupric or cuprous sulfate, ammonium-vanadate or the like that act as a catal tic agent.

Instead o preparin the paper with a coating of gelatine a fiIm of agar-agar, albumin, or other substances may be used. The nitro-sulfonic acid mentioned in this example of the process and the amine can be replaced by other analogous compounds.

I claim:

1. Process of the kind described consisting in treating organic fibers with nit-ro-naphthalene compounds which contain a nitro group and a sulfonic acid-group, and in exposing the fibers thus treated to light.

2. Process of the kind described consisting in treating organic fibers with nitro-naphthalene compounds which contain a plurality of nitro-groups and a sulfonic acid-group, antll in exposing the fibers thus treated to ll lt.

3. Process of the kind described consisting in treating organic fibers with nit-ro-naphthalene compounds which contain a plurality of nitro-groups and of sulfonic acid-groups,

and in exposing the fibers thus treated to li fht.

4. Process of the kind described consisting in treating organic fibers with nitro-naphthalene compounds which contain :1. nitrogroup and a sulfonic acid-group, also treating the fibers with an aromatic amine, and exposing the fibers thus treated to light.

5. Process of the kind described consisting in treating organic fiber articles with nitronaphthaline compounds that contain a nitrogroup and a sulfonic acid-group, also treating the fibers with an aromatic amine, producing a pattern on the article by exposing it to light that passes through transparent parts 0 a screen, and fixing the pattern after exposure of the article to light by Washing the article.

6. Process of the kind described consisting in treating paper coated with nitro-naphthalene compounds that contain a nitrogroup and a sulfonic acid-group, and in exposing the treated paper to light through a photographic negative and washing said treated paper.

7. Process of the kind described consisting in treating paper coated with a nitro-naphthalene compound containing a nitro-group, a sulfonic acid-group and a catalytic agent, exposing the paper thus treated to light through a photographic negative, and fixing the pattern thus produced by actinic rays on the paper by washing the same.

In testimony whereof I have affixed my signature.

NIKOLAI IVOROSHTZOW. 

